7
7 AHM September 2005 Data Visualization: Multiple Users ● Hard to collaborate with other users ● Usually – must all crowd around one machine ● Unless a large display is available ● One person “driving” – others are passive ● System is not assisting with collaboration

8
8 AHM September 2005 Data Visualization: Specialist Equipment ● May require specialist computer ● Capable of displaying complex data ● Prohibitively expensive to own ● User may need to move to machine ● Problem if only one machine ● Overloaded – too slow to be usable ● All displays are in use ● What if it breaks?

17
17 AHM September 2005 Service Discovery ● Servers are “advertised” on the network ● Using standardised methods ● UDDI, Grid/Web Services ● We can reuse the work of other people ● UDDI4J, Apache Axis, Globus ● Human user can see list of servers ● Select most appropriate one ● Consider speed, memory, bandwidth... ● May already have your required data on it ● Or automatically select with a heuristic